CN101055283A - Three-range current recording and balance analysis method and device - Google Patents
Three-range current recording and balance analysis method and device Download PDFInfo
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- CN101055283A CN101055283A CNA2007100154758A CN200710015475A CN101055283A CN 101055283 A CN101055283 A CN 101055283A CN A2007100154758 A CNA2007100154758 A CN A2007100154758A CN 200710015475 A CN200710015475 A CN 200710015475A CN 101055283 A CN101055283 A CN 101055283A
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Abstract
The invention provides a method and apparatus for recording and equally analyzing three-phase current, including: detecting continuously and storing three-phase current data by a distribution room; retrieving periodically storage data; reading and processing three-phase current data using computed installed with three-phase current analysis software; calculating imbalance rate of three-phase current; obtaining data table, three-phase current variation curve and imbalance rate variation curve notated by apparatus number and detecting time; inquiring and analyzing integrally the data and curve, so as to obtain imbalance degree of three-phase power load. The apparatus includes a three-phase current detection storage apparatus and a computer. The invention is capable of analyzing and managing line loss control of, and can be applicable for analytical adjustment of three-phase load imbalance of rural area low-voltage distribution system and control management of transmission line loss.
Description
Technical field
The present invention relates to the analysis adjustment of low voltage electric network three-phrase burden balance, be specifically related to the method and the device of a kind of three-phase current record and equilibrium analysis.
Background technology
In the distribution system of rural low voltage network, owing to adopt three phase supply, and actual user's single-phase load is more, often there is the load unbalanced operation phenomenon of three-phase power, cause the increase of substation transformer loss and line loss, when serious even circuit blows, transformer burns, bring the decline of electric network reliability and stability.In the management of substation transformer operation, in order to detect the uneven degree of actual three-phase power load (electric current), so that in time take effective control measure, need regular current value to carry out collection analysis, so that provide science foundation accurately for adjusting three-phrase burden balance to three-phase load.In the management of countryside low-voltage electric distribution system, take the rural power worker regularly to arrive switchgear building (platform district) usually and observe the also method of write by hand three-phase electricity flow valuve at present.This method has the following disadvantages:
1, the workload of checking meter is big, wastes time and energy, and inefficiency is made mistakes easily.
2, randomness is big, not science.Because electricity consumption time disunities such as household electrical appliance such as domestic lighting and rural area process equipment, electrician's work hours mostly by day, the time of checking meter is unfixing yet, the peak or the low ebb of this phase load may be run into, the three-phase line burden apportionment situation of low-voltage distribution system can not be accurately, intactly reflected.
3, data acquisition is excessive at interval, and data sample is very few.
4, data analysis contrasts not visual pattern, is difficult to describe and reflect the load distribution situation of three-phase line.
Summary of the invention
Goal of the invention of the present invention is: overcome the deficiency that prior art exists, detection record when a kind of can growing automatically is provided, data acquisition amount are big, simple to operate, the three-phase current record and the equilibrium analysis method that can intuitively show three-phase current electric current and unbalance factor change curve waveform provide a kind of three-phase current record and equilibrium analysis device for realizing that said method designs simultaneously.
Technical scheme of the present invention is: the method for a kind of three-phase current record and equilibrium analysis is provided, comprises the steps:
(1) switchgear building continuous detecting and store the three-phase current Value Data;
(2) regularly fetch three-phase electricity flow valuve storage data;
(3) utilize the computer that the three-phase current analysis software is installed to read and handle the three-phase current Value Data;
(4) calculate the three-phase current unbalance rate;
(5) obtain data form, three-phase current change curve and three-phase current unbalance rate change curve by device number and detection time sign;
(6) inquiry and the above-mentioned data of analysis-by-synthesis, curve are to know that each switchgear building or platform district are in the load unbalanced degree of the three-phase power of different time sections.
The present invention also provides a kind of three-phase current record and equilibrium analysis device for realizing that such scheme designs, and comprises three-phase current detection storage apparatus and host computer; Described three-phase current detection storage apparatus comprises detecting unit, storage unit, display unit, parameter set unit, power supply unit and microprocessor unit, wherein said detecting unit, storage unit, display unit, parameter set unit connect with microprocessor unit respectively, and the same respectively detecting unit of power supply unit, storage unit, display unit, parameter set unit is connected with microprocessor unit and provide working power for it; Described host computer is the computer that the three-phase current analysis software is installed.
Further, described storage unit adopts USB flash disk.
Described host computer is desktop computer, portable notebook computer or palm PC PDA.
The present invention has following advantage compared with the prior art:
1, detection of stored three-phase current data in the time of can growing automatically, storage data volume are big; Rural power worker only need regularly fetch image data, just can significantly reduce workload in the enterprising line data analysis of the computer that the three-phase current analysis software is installed, and has improved work efficiency.
2, adopt computer software analysis to calculate the three-phase current unbalance rate, show three-phase current and three-phase current unbalance rate change curve, visual pattern, three-phase line load distribution situation that can complete reflection low-voltage distribution system provides science to analyze foundation accurately for adjusting three-phrase burden balance.
Description of drawings
Fig. 1 is the workflow diagram of three-phase current record and equilibrium analysis method.
Fig. 2 is the structural principle block scheme of three-phase current record and equilibrium analysis device.
Fig. 3 is the structural principle block scheme of three-phase current record and equilibrium analysis device embodiment;
Among the figure: 1-mutual inductor A, 2-mutual inductor B, 3-mutual inductor C, 4-operational amplifier A, 5-operational amplifier B, 6-operational amplifier C, the 7-single-chip microcomputer, the 8-parameter is provided with keyboard, the 9-display screen, 10-U coils interface, 11-power module, 12-three-phase current detection storage apparatus, 1 3-host computer.
Fig. 4 is the function and the workflow synoptic diagram thereof of three-phase current analysis software.
Embodiment
The invention will be further described below in conjunction with drawings and Examples.
In the workflow diagram of Fig. 1 three-phase current record and equilibrium analysis method: at first three-phase current detection storage apparatus is installed in each switchgear building or platform district, continuous detecting three-phase electricity flow valuve and with data storage in microprocessor; Rural power worker regularly copies or fetches three-phase electricity flow valuve storage data to each switchgear building or platform district; On the computer that the three-phase current analysis software is installed, utilize the three-phase current analysis software to read and handle the three-phase current Value Data, calculate the three-phase current unbalance rate, and obtain three-phase current and three-phase current unbalance rate data form, three-phase current change curve and three-phase current unbalance rate change curve by device number and detection time sign; The staff who is responsible for the management of rural power grids line loss inquires about the also above-mentioned data of analysis-by-synthesis, curve, both can know that each switchgear building or platform district were in the load unbalanced degree of the three-phase power of different time sections.
In the structural principle block scheme of Fig. 2 three-phase current record and equilibrium analysis device: three-phase current record and equilibrium analysis device comprise three-phase current detection storage apparatus and host computer.Wherein three-phase current detection storage apparatus comprises detecting unit, storage unit, display unit, parameter set unit, microprocessor unit and power supply unit (not drawing among the figure), described detecting unit is finished the acquisition process three-phase current signal and three-phase current signal is input to microprocessor unit, outputing to storage unit after microprocessor unit carries out A/D analog to digital conversion and calculation process and is formatted into text the three-phase current signal of importing stores, outputing to display unit simultaneously shows, parameter set unit is finished the setting to the relevant acquisition parameter of microprocessor unit, and power supply unit provides dc supply for each functional unit of three-phase current detection storage apparatus; Host computer comprises the three-phase current analysis software of installation and operation in computer and the computer, finishes the three-phase current data that read three-phase current detection storage apparatus storage and analyzes, calculates, shows, inquires about and handle.
In the structural principle block scheme of Fig. 3 three-phase current record and equilibrium analysis device embodiment, three-phase current detection storage apparatus 12 adopts the high precision clamp current transformer to detect and gathers electrical network three phase supply current signal, wherein Reference numeral is respectively 1,2,3 mutual inductor A, mutual inductor B and mutual inductor C gather A respectively, B, the C three-phase current signal, be respectively 4 through Reference numeral successively, 5,6 operational amplifier A, operational amplifier B, after operational amplifier C carries out the line style amplification and conditioning of signal, being input to single-chip microcomputer 7 carries out the row operation of going forward side by side of A/D analog to digital conversion and handles, on display screen 9, demonstrate the three-phase electricity flow valuve and the collection date of this device number then, time, parameter is provided with keyboard 8 and is used to gather the date, time, gather isoparametric setting of memory cycle, power module 11 is to offer three-phase current detection storage apparatus behind the dc supply with single-phase AC 220V power rectifier; Display screen 9 adopts the large-screen lc screen, and operational amplifier A, operational amplifier B, operational amplifier C adopt high precision, low drifting operating amplifier LM324, also can adopt the chip of integrated a plurality of operational amplifiers; Single-chip microcomputer 7 adopts 16 single-chip microcomputer MSP430F1232 at a high speed, by the calculation process of programming realization to three-phase current signal, single-chip microcomputer 7 mainboards drive the Universal USB interface module, can external USB flash disk and with the three-phase current data with the normative text form by device number and detection time the sign back regularly be stored on the USB flash disk, the storage medium that USB flash disk adopts is that flash memory is Flash Memory, only need receive just storage read-write data independently of USB interface; As the rural power worker regularly to each switchgear building or platform district copy or after changing USB flash disk and fetching three-phase electricity flow valuve storage data, can utilize the USB interface of host computer 12 read in the USB flash disk " module data " file of storing and convert database format to, carry out the three-phase current unbalance rate and calculate, obtain three-phase current and the three-phase current unbalance rate data form that indicates by device number and detection time and show the three-phase current change curve and three-phase current unbalance rate change curve.The horizontal form of data form is respectively with " device number ", " detection time ", " A phase current ", " B phase current ", " C phase current ", " current imbalance rate " is title, vertical form press device number and certain year time on date of some time branch mark in such a month, and on such a day, continuously listed three-phase current and three-phase current unbalance rate data as 1 minute for the interval with reference to collection period, the line loss analyzing managerial personnel can very conveniently analyze above-mentioned data intuitively, statistics, inquiry, handle, also can export to the EXCEL electronic form file of standard, report and print for transmission; Host computer 12 can adopt desktop computer or the portable notebook computer that the three-phase current analysis software is installed, also can adopt the palm PC PDA of embedded three-phase current analysis software, when host computer 12 adopts portable notebook computer or palm PC PDA, can utilize its USB interface directly to copy three-phase current record and equilibrium analysis device USB flash disk store data inside, also can directly move the three-phase current analysis software on the spot at switchgear building, carrying out the load unbalanced analysis and judgement of three-phase power also in time adjusts, to reduce the load unbalanced rate of three-phase power, improve power supply quality.
The current measurement of three-phase current detection storage apparatus is owing to adopted current detecting scope 0-1000A, precision to reach 0.5 grade split core type current transformer, installing/dismounting is very convenient, like this electrician just can be between each switchgear building itinerant monitor system, both improved work quality, increase work efficiency again; High-performance singlechip chip and 160 * 80 Chinese character big screen LCDs are when detecting in real time and showing test value, also can write down and store one group of three-phase electricity flow valuve and deposit USB flash disk in, can store and be no less than 1 year the data of (by the decision of USB flash disk capacity) continuously every regular hour (can be provided with interval time) with text formatting.
Three-phase current detection storage apparatus is can 24 hours round-the-clock to the three-phase current tracking and monitoring, and it is stored in the USB flash disk, electrician two weeks or one month as required fetches USB flash disk come or copy is returned, with data conversion storage to host computer, by the upper computer software program data are read out, calculate tri-phase unbalance factor, and the size of three-phase current and the tri-phase unbalance factor form with curve is showed intuitively, thereby adjust the foundation that load provides science for the electrician.
In the function and workflow synoptic diagram thereof of Fig. 4 three-phase current analysis software: on the computer that the three-phase current analysis software is installed, click " three-phase current analytic system " icon, double-click operation and enter program interface; With depositing the USB interface of the USB flash disk insertion computer of image data, click " reading of data " menu, find the drive path of USB flash disk and the file and the click " opening " of " module data " by name; This moment begin to read image data in program, Automatic Program by formula:
Three-phase current unbalance rate=(three-phase current vector and/three-phase current scalar sum) * 100% calculates the three-phase current unbalance rate and generates a data form of filling in proper order according to data collection cycle intervening sequences and device number and can drag scroll bar by " device number ", " detection time ", " A phase current ", " B phase current ", " C phase current ", " current imbalance rate " successively and browses in chronological order; Be that horizontal ordinate, current amplitude are that ordinate generates the three-phase current curve simultaneously with time, clicking " three-phase current curve " can change by the three-phase current of watching 24 hours this days every day; With time is that horizontal ordinate, current imbalance rate are that ordinate generates the three-phase current unbalance rate curve, and clicking " unbalance factor curve " menu can be by the unbalance factor change curve of watching 24 hours this days every day; Program provides the operation indicating of data query, analysis, derivation simultaneously, click " data query ", can be by date, the data be concerned about of time period, the inquiry of current imbalance rate, click the EXCEL form that " being directed at EXCEL " can export to the raw data of reading in or the data that according to condition inquire standard, click " total data " and can watch all image data.
The detection record when microcomputer that the present invention has realized the rural power grids three-phase currents is long automatically, intuitively show three-phase current and unbalance factor change curve by powerful upper computer software, science is accurate, the traditional-handwork record current value operating type that vast rural power worker has been broken away from waste time and energy, realize the microcomputer analysis and the management of the line loss control of countryside low-voltage electric distribution system, can be widely used in the control and management of unbalanced analysis adjustment of rural low voltage network distribution system three-phase load and grid line loss.
Claims (4)
1, the method for a kind of three-phase current record and equilibrium analysis is characterized in that comprising the steps:
(1) switchgear building continuous detecting and store the three-phase current Value Data;
(2) regularly fetch three-phase electricity flow valuve storage data;
(3) utilize the computer that the three-phase current analysis software is installed to read and handle the three-phase current Value Data;
(4) calculate the three-phase current unbalance rate;
(5) obtain data form, three-phase current change curve and three-phase current unbalance rate change curve by device number and detection time sign;
(6) inquiry and the above-mentioned data of analysis-by-synthesis, curve are to know that each switchgear building or platform district are in the load unbalanced degree of the three-phase power of different time sections.
2, a kind of three-phase current record and equilibrium analysis device comprise three-phase current detection storage apparatus and host computer; Described three-phase current detection storage apparatus comprises detecting unit, storage unit, display unit, parameter set unit, power supply unit and microprocessor unit, wherein said detecting unit, storage unit, display unit, parameter set unit connect with microprocessor unit respectively, and the same respectively detecting unit of power supply unit, storage unit, display unit, parameter set unit is connected with microprocessor unit and provide working power for it; Described host computer is the computer that the three-phase current analysis software is installed.
3, according to described three-phase current record of claim 2 and equilibrium analysis device, it is characterized in that described storage unit adopts USB flash disk.
4, according to described three-phase current record of claim 2 and equilibrium analysis device, it is characterized in that described host computer is desktop computer, portable notebook computer or palm PC PDA.
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| CNA2007100154758A CN101055283A (en) | 2007-04-30 | 2007-04-30 | Three-range current recording and balance analysis method and device |
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Cited By (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103116088A (en) * | 2013-01-14 | 2013-05-22 | 湖北省电力公司电力科学研究院 | Large-scale transformer three-phase parameter inconsistent operation analysis method |
| CN103364723A (en) * | 2012-04-05 | 2013-10-23 | 北京光耀能源技术股份有限公司 | Running state analysis method for aerogenerator based on voltage and current balance |
| CN105117986A (en) * | 2015-09-25 | 2015-12-02 | 国网湖北节能服务有限公司 | Low voltage network line loss calculating method considering the imbalance degree |
| CN105591396A (en) * | 2016-02-29 | 2016-05-18 | 国家电网公司 | Low-voltage distribution line distribution transformer three-phase unbalance protection method and device |
| CN105629050A (en) * | 2015-12-24 | 2016-06-01 | 万进 | Energy-saving power transmission line loss and fault monitoring device |
| CN105785205A (en) * | 2016-05-16 | 2016-07-20 | 上海欧忆智能网络有限公司 | Three-phase unbalanced load on-line monitoring system and device |
| CN106058854A (en) * | 2016-06-02 | 2016-10-26 | 国网天津市电力公司 | Method for evaluating current three-phase unbalance degree of distribution network |
| CN106786681A (en) * | 2017-01-12 | 2017-05-31 | 湖南长高思瑞自动化有限公司 | Low-voltage platform area becomes threephase load automatic-balancing system and its automatic balancing method |
| CN109787255A (en) * | 2019-02-19 | 2019-05-21 | 国网江西省电力有限公司电力科学研究院 | Power distribution station load adjustment method and device |
| CN110659267A (en) * | 2019-07-30 | 2020-01-07 | 浙江华云信息科技有限公司 | Douglas-Puke-based current three-phase imbalance curve simplification method |
| CN110967584A (en) * | 2019-12-18 | 2020-04-07 | 国网山东省电力公司五莲县供电公司 | On-site electric energy loss testing method and device |
| CN112736938A (en) * | 2020-12-28 | 2021-04-30 | 广东电网有限责任公司韶关供电局 | Load commutation method and device in transformer area |
| CN114280385A (en) * | 2021-12-30 | 2022-04-05 | 北京京能高安屯燃气热电有限责任公司 | Service power three-phase voltage balance judgment method based on real-time monitoring |
-
2007
- 2007-04-30 CN CNA2007100154758A patent/CN101055283A/en active Pending
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103364723A (en) * | 2012-04-05 | 2013-10-23 | 北京光耀能源技术股份有限公司 | Running state analysis method for aerogenerator based on voltage and current balance |
| CN103364723B (en) * | 2012-04-05 | 2015-12-16 | 北京光耀能源技术股份有限公司 | Based on the running status of wind generator analytical approach of electric current and voltage balance |
| CN103116088A (en) * | 2013-01-14 | 2013-05-22 | 湖北省电力公司电力科学研究院 | Large-scale transformer three-phase parameter inconsistent operation analysis method |
| CN103116088B (en) * | 2013-01-14 | 2014-12-10 | 湖北省电力公司电力科学研究院 | Large-scale transformer three-phase parameter inconsistent operation analysis method |
| CN105117986A (en) * | 2015-09-25 | 2015-12-02 | 国网湖北节能服务有限公司 | Low voltage network line loss calculating method considering the imbalance degree |
| CN105629050B (en) * | 2015-12-24 | 2019-06-28 | 万进 | A kind of energy-saving transmission line losses and failure monitoring device |
| CN105629050A (en) * | 2015-12-24 | 2016-06-01 | 万进 | Energy-saving power transmission line loss and fault monitoring device |
| CN105591396B (en) * | 2016-02-29 | 2018-06-26 | 国家电网公司 | The three-phase imbalance guard method of the distribution transformer of low-voltage distributing line and device |
| CN105591396A (en) * | 2016-02-29 | 2016-05-18 | 国家电网公司 | Low-voltage distribution line distribution transformer three-phase unbalance protection method and device |
| CN105785205A (en) * | 2016-05-16 | 2016-07-20 | 上海欧忆智能网络有限公司 | Three-phase unbalanced load on-line monitoring system and device |
| CN106058854A (en) * | 2016-06-02 | 2016-10-26 | 国网天津市电力公司 | Method for evaluating current three-phase unbalance degree of distribution network |
| CN106058854B (en) * | 2016-06-02 | 2019-01-15 | 国网天津市电力公司 | A kind of evaluation method of distribution current three-phase degree of unbalancedness |
| CN106786681A (en) * | 2017-01-12 | 2017-05-31 | 湖南长高思瑞自动化有限公司 | Low-voltage platform area becomes threephase load automatic-balancing system and its automatic balancing method |
| CN109787255A (en) * | 2019-02-19 | 2019-05-21 | 国网江西省电力有限公司电力科学研究院 | Power distribution station load adjustment method and device |
| CN109787255B (en) * | 2019-02-19 | 2020-08-11 | 国网江西省电力有限公司电力科学研究院 | Power distribution station load adjusting method and device |
| CN110659267A (en) * | 2019-07-30 | 2020-01-07 | 浙江华云信息科技有限公司 | Douglas-Puke-based current three-phase imbalance curve simplification method |
| CN110967584A (en) * | 2019-12-18 | 2020-04-07 | 国网山东省电力公司五莲县供电公司 | On-site electric energy loss testing method and device |
| CN112736938A (en) * | 2020-12-28 | 2021-04-30 | 广东电网有限责任公司韶关供电局 | Load commutation method and device in transformer area |
| CN114280385A (en) * | 2021-12-30 | 2022-04-05 | 北京京能高安屯燃气热电有限责任公司 | Service power three-phase voltage balance judgment method based on real-time monitoring |
| CN114280385B (en) * | 2021-12-30 | 2023-12-26 | 北京京能高安屯燃气热电有限责任公司 | Real-time monitoring-based station service three-phase voltage balance judging method |
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